1. Field of the Invention
This invention relates to improvements in portable fire extinguishers. More particularly, the present invention relates to a fire extinguisher that allows for external mixing, fluffing, actuating or stirring of the powder within the chamber to provide anti-bridging of the powder to keep it in a liquefied state, a larger opening in the chamber to allow easier filling of the chamber and a CO2 canister that is located external to the extinguisher chamber.
2. Description of Related Art including information disclosed under 37 CFR 1.97 and 1.98
Most portable fire extinguishers are of a similar design where the fire extinguishing powder is contained in a pressurized chamber. Fire extinguishers of this type require scheduled maintenance because the powder within the chamber can settle and cake preventing it from being dispensed when needed. The pressure within the chamber may also leak over time and be insufficient to propel the powder out of the dispensing nozzle. A further limitation, based upon this design is due to the pressurized condition of the chamber, powder is placed into the chamber in a small opening in the top of the extinguisher. This scheduled maintenance allow moisture intrusion causing caking. Current extinguishers can only be service by trained certified technicians, and the certification is issued by the fire marshal for each state.
Current extinguishers are open to wear and tear because of the constant pressure and tear down process. When serviced they are fires into a recycling chamber and all the parts must be disassembled and cleaned. All the pressure rings must be replaced and every part must them be re-assembled with new powder being placed within the chamber prior to pressurizing the chamber. The servicing of current fire extinguishers often creates more wear and tear on the fire extinguisher than when it is used to extinguish a fire.
U.S. Pat. No. 6,189,624 issued to James on Feb. 20, 2001 and Japan Patent Number JP 9,225,056 issued to Yamazaki Tomoki on Sep. 2, 1997 discloses fire extinguishing mechanisms where the chamber is not continuously pressurized, and the pressurized chamber is a separate entity integrated within the chamber. While these patents disclose a separate pressurized canister, the canister is not located in a position that is easy to service, replace, or inspect. This minimizes the ability determine the charge level of the CO2 cartridge.
U.S. Pat. No. 2,541,554 issued to C H Smith on Feb. 13, 1951 and Russian Patent Number RU 2,209,101 issued to Glavatski G. D. Et Al. Nov. 2, 2002 discloses a fire extinguisher with external CO2 gas cartridge. In the case US '554 the CO2 gas cartridge sits on top of the fire extinguisher chamber and is not integrated within the handle of the fire extinguisher. In the case of RU '101 the CO2 gas cartridge is external to the extinguisher and is connected to the extinguisher with a pipe or hose. While both of these patents disclose a CO2 cartridge that is external to the chamber, neither of them is placed in the handle to allow a configuration of the fire extinguisher that is simple to inspect and replace.
Due to the pressurized condition that exists with pressurized fire extinguishers, the opening where powder is placed into the extinguisher is limited due to the structural requirement to maintain pressure within the chamber at all times. The proposed application eliminates this need by providing an external CO2 gas cartridge, thus allowing the chamber to exist in a normally un-pressurized condition. Because the chamber is not under pressure the top opening of the extinguisher can be enlarged to allow easier filling of the fire extinguisher with powder, or checking the amount and or condition of the powder within the chamber.
What is needed is a fire extinguisher with an external gas cartridge where the gas cartridge is located in the handle, a fluffer is accessible from outside the chamber, and the chamber has an enlarged top opening for filling the extinguisher. The proposed fire extinguisher provides this solution by providing a fire extinguisher with an external gas cartridge, external fluffer and large opening.